The invention involves a mounting for oblong structures such as cables, hoses, or the like, which have an electrical shielding and are, in the usage positionxe2x80x94if necessary, after a removal of the shielding by stripping the insulationxe2x80x94in electrical connection with the mounting via an electrically conducting insert that has a clamping finger, where the mounting has a receptacle opening for inserting or guiding through the oblong structure and for receiving the electrically conducting insert, and this insert has a mounting ring with axially spaced apart clamping fingers.
A similar arrangement or mounting of this type is known from the patent DE-OS 17 65 795. The clamping fingers of the spring-insert are, in this known solution, deformed by a conical area of a mounting sheath and by an axial movement, radially to the inside against the shielding sheath. The quality of the contact and the pressing force of the respective clamping finger on the shielding sheath is thus a function of the length of the axial movement and the cone angle as well as the length of the clamping fingers. If a screw connection necessary in this case for the axial adjustment can for some reason not be performed with a sufficiently large axial adjustment movement over a sufficiently large axial length, a good contact result is jeopardized or not even present.
A similar arrangement is known from the patent DE-GM 74 34 418. In this, the clamping fingers running approximately coaxially on their inside have a conical shape that tapers from their starting position towards their open end and the entire insert must be shoved, for an axial adjustment of the cable and a mounting that grasps it, in the axial direction into a constriction, such that in turn the clamping fingers because of their conical outer shape are deformed in the radial direction against the electrical shielding sheath and are pressed against it. Thus, also in this case, the quality of the contact is a function of the axial adjustment and the cone angle, i.e. also in this case, a relatively large axial adjustment is necessary in order to generate a sufficiently good contact.
Therefore, the object of the invention is to create a mounting of the type named at the beginning in which a secure contact between the oblong structure and its shielding sheath and the insert that has the clamping fingers, can be achieved independently of an axial movement, when the insert is located in its mounting position.
In order to achieve this purpose, it is provided that on the outer side of the clamping fingers functioning for the contact, at a distance from their open ends which function as a contact position, and at a distance from the mounting ring, at least one projection is respectively arranged, such that the projections, in the relaxed positionxe2x80x94i.e. when the insert is located, for example, outside of the reception opening of the mounting, extend up to a sheath circle or sheath cylinder that has a diameter that is larger than the corresponding dimension of the inner cross-section of the receptacle opening of the mounting, and that the projections are supported, when an insert is inserted into the reception opening, on the wall of the reception opening under the restoring force of the radially inwardly bent clamping fingers in this usage position. In this way, it can be achieved that when introducing this insert or spring insert into the receptacle opening of the mounting, the outside projections cause a corresponding swinging and bending, radially inwardly of the clamping and contact fingers that are carried by the mounting ring, such that the free ends of these clamping fingers are also swung inwardly to the furthest possible extent, independently of any cone surface or an axial extension of some movement. It is sufficient to bring the area provided with the projections into the receptacle opening of the mounting, in order to achieve the specified swinging of the clamping fingers by a dimension determined in advancexe2x80x94independent of the size of the projections and their position relative to the ends of the clamping fingers. Thus, a very simple mounting results with a desired predetermined approach of the open contact ends of the clamping or contact fingers to the shielding sheath or the contact position, so that it is already possible beforehand to coordinate the radial dimension of the projections on the one hand, and their distance from the ends of the contact fingers on the other hand, to the cross-sectional dimension of the respective oblong structure and the desired pressing force.
It is expedient when the clamping fingers are uninterrupted or continuous below their projections. Thus, the force exerted on the clamping finger by the projection when inserting it into the receptacle opening is also practically completely transferred to the clamping finger.
A good force transfer from the projections to the clamping fingers results when the projections are massive on the clamping fingers or consist of a solid material with them, i.e. at the position of the projections, the clamping fingers are thickened around them in their respective cross-section. In this way, it can even be better prevented that the projections themselves possibly deform when the insert and the contact finger are introduced into the receptacle opening. Furthermore, in this way, the stability of the clamping fingers is increased.
The separation distance of the outside projections of the clamping fingers from the mounting ring can be smaller than the separation distance of the projections from the free ends of the clamping fingers. The free ends are bent corresponding further radially inwardly when the projections come into the receptacle opening.
For example, the separation distance of the projections from the free ends of the clamping fingers can be approximately xc2xe to ⅘ of the entire length of the clamping finger extending out from the mounting ring. An additional practical dimension can consist in that the radial extension of the projections to the outside of the clamping fingers amounts to the radial thickness or size of these clamping or contact fingers. By the combination of such dimensions, the radial inwards movement of the open ends of the clamping fingers can be predetermined to a desired dimension, so that the contact pressure is also influenced by it, when an oblong structure runs between these clamping or contact fingers. At the same time, the force necessary for swinging or bending can be influenced by these dimensions and limited to a tolerable size.
For a mounting of the insert into a receptacle opening of the mounting, which is as easy and smooth-running as possible, it is expedient the transition from the outside of the clamping fingers to the projection, or at least the edge of the respective projection which is facing the open end of the respective clamping finger, is beveled such that the axial extension of the projection from the clamping finger decreases in the radial direction toward the outside. The projections can thus have a sloping surface that increases to their largest radial extension and that makes it easier to introduce the insert into the receptacle opening so that this introduction movement functions for the radial inward swinging of the clamping fingers.
The sloping surface increasing to the largest radial expansion of the projection can thereby be linear in cross-section and/or curved in a convex or concave manner. Thus, a certain transition can be provided for the introduction movement into the receptacle opening.
The clamping fingers can be arranged in the undeformed starting positionxe2x80x94i.e. outside of the receptacle opening of the mountingxe2x80x94approximately cylindrically and in particular have a bend on their inside corresponding to the surface of this imaginary cylinder. In this way, a good fit is simultaneously possible on an oblong structure that is as a rule cylindrical, for example, a cable that has been stripped of its insulation or the like, having the largest possible positioning surface.
It is, however, also or additionally possible, that the ends of the clamping fingers separate from each other at least in the undeformed starting position, forming a lead-in funnel. This makes easier the insertion of the oblong structure from the open end of the clamping fingers, in particular, also even before the insertion into the actual mounting and its receptacle opening. Along with that, the insertion of the oblong structure from the mounting is, of course, possible in the same way and also in the pre-mounted position.
The mounting ring can extend beyond the projections in the radial direction. This is especially advantageous for the attachment of the insert using this mounting ring.
For example, the mounting ring can have a stopper and/or a catch projection or latching connection for axially attaching onto the edge or in the inside of the receptacle opening. This allows a simple insertion of the clamping or contact insert and expedient clipping into a corresponding groove that can receive the latching connection or catch projection.
The insert can be manufactured in an especially cost-effective manner when the insert consisting of clamping fingers and mounting ring is constructed as a single piece.
An additional embodiment is possible in making it such that this electrically conducting insert consists of an electrically conducting synthetic material or out of a synthetic material that is provided at least on the surface locally with an electrically conducting layer, for example, out of metallized synthetic material or synthetic material that is coated or vapor deposited with metal and/or with synthetic material provided with metal inlays projecting from it. This makes possible the manufacture of the contact insert in the injection molding process practically in one work step. Furthermore, this material has the advantage of creating a gentle positioning on the electrical shielding sheath of a cable or hose and ruling out, to the greatest extent possible, any damages to this shielding sheath under larger pressure forces and possible relative movements between the clamping fingers and the cable or hose.